There have been recently introduced useful cable articles from materials that are composite and thus cannot readily be plastically deformed to a new shape. Common examples of these materials include fiber reinforced composites which are attractive due to their improved mechanical properties relative to metals but are primarily elastic in their stress strain response. Composite cables containing fiber reinforced polymer wires are known in the art, as are composite cables containing ceramic fiber reinforced metal wires, see, e.g., U.S. Pat. Nos. 6,559,385 and 7,093,416; and Published PCT Application WO 97/00976.
One use of composite cables (e.g., cables containing polymer matrix composite or metal matrix composite wires) is as a reinforcing member in bare (i.e. non-insulated) cables used for above-ground electrical power transmission. Although bare electrical power transmission cables including aluminum matrix composite wires are known, for some applications there is a continuing desire to obtain improved cable properties. For example, bare electrical power transmission cables are generally believed to be unsuitable for use in underground or underwater electrical power transmission applications.
In addition, in some applications, it may be desirable to use stranded composite cables for electrical power transmission. Cable stranding is a process in which individual ductile wires are combined, typically in a helical arrangement, to produce a finished cable. See, e.g., U.S. Pat. Nos. 5,171,942 and 5,554,826. Helically stranded power transmission cables are typically produced from ductile metals such as steel, aluminum, or copper. In some cases, such as bare overhead electrical power transmission cables, a helically stranded wire core is surrounded by a wire conductor layer. The helically stranded wire core could comprise ductile metal wires made from a first material such as steel, for example, and the outer power conducting layer could comprise ductile metal wires made from another material such as aluminum, for example. In some cases, the helically stranded wire core may be a pre-stranded cable used as an input material to the manufacture of a larger diameter electrical power transmission cable. Helically stranded cables generally may comprise as few as seven individual wires to more common constructions containing 50 or more wires.
The art continually searches for improved composite cables for use in underground or underwater (i.e., submersible) electrical power transmission applications. The art also searches for improved stranded composite power transmission cables, and for improved methods of making and using stranded composite cables.